Torchieres have become highly popular lighting devices in recent years, typically due to their low cost and bright yet soft lighting characteristics. Typically, torchieres include a reflective bowl mounted on a pole exceeding the height of a normal adult. A tubular halogen light bulb is horizontally disposed inside the bowl where it cannot be seen by persons in the room, and the very bright light of the halogen lighting element is directed upward so as to reflect from the ceiling with the soft dispersed appearance of indirect lighting.
The halogen lighting elements used in torchieres are typically expensive and hard to install due to their sensitivity to skin oils. Two problems occur in their use: for one, they get extremely hot in use--so hot, in fact, that a flammable fabric draped or blown over the bowl, or a toy thrown into the bowl, will catch fire in a short time. For that reason, Underwriters' Laboratories approval for unprotected halogen lighting elements has been limited to elements not exceeding 150 W, although the market demands at least 300 W elements for sufficient light intensity.
A number of expedients to allow the use of higher-wattage halogen lighting elements have been proposed, such as spacer grids and glass plates supported inwardly of the rim of the bowl to provide a cooling air circulation. None of these solutions are quite satisfactory, however: either the grid itself or the mountings create shadow patterns that detract from the evenness of torchiere lighting. An uneven pattern is also produced by the horizontal orientation of the halogen lighting element.
The horizontal orientation of the conventional halogen lighting element also causes a second problem: Because the center of the horizontal element overlies a non-reflective part of a typical torchiere bowl, about 20% of the light output of the element is lost for indirect lighting purposes. Thus a torchiere with a 300 W, 4800 lumen element actually puts out a usable indirect lighting intensity of only 4200 lumens, which approximately corresponds to the total output of a 250 W element.
Another disadvantage of conventional torchieres is the fact that, due to their cost, spare halogen bulbs are usually not readily available in most households. Therefore, if a bulb burns out, the torchiere is not usable until a replacement bulb has been purchased and installed. This can be awkward or difficult at night, when the torchiere is most likely to be in use.